Solve using Elimination 3x+y=-9 y=5x+7

Mathematics

1 answer:

valentinak56 [21]2 years ago

7 0

Answer

x=-2 and y=-3

Step-by-step explanation:

Step: Solvey=5x+7for y:

Step: Substitute5x+7 for y in 3x+y=−9:

3x+y=−9

3x+5x+7=−9

8x+7=−9(Simplify both sides of the equation)

8x+7+−7=−9+−7(Add -7 to both sides)

8x=−16

8x/8=−16/8

(Divide both sides by 8)

x=−2

Step: Substitute−2 for x in y=5x+7:

y=5x+7

y=(5)(−2)+7

y=−3(Simplify both sides of the equation)

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